Probing high-redshift galaxies with Lyα\alpha intensity mapping

We present a study of the cosmological Ly$\alpha$ emission signal at $z > 4$. Our goal is to predict the power spectrum of the spatial fluctuations that could be observed by an intensity mapping survey. The model uses the latest data from the HST legacy fields and the abundance matching technique to associate UV emission and dust properties with the halos, computing the emission from the interstellar medium (ISM) of galaxies and the intergalactic medium (IGM), including the effects of reionization, self-consistently. The Ly$\alpha$ intensity from the diffuse IGM emission is 1.3 (2.0) times more intense than the ISM emission at $z = 4(7)$; both components are fair tracers of the star-forming galaxy distribution. However the power spectrum is dominated by ISM emission on small scales ($k > 0.01 h{\rm Mpc}^{-1}$) with shot noise being significant only above $k = 1 h{\rm Mpc}^{-1}$. At very lange scales ($k < 0.01h{\rm Mpc}^{-1}$) diffuse IGM emission becomes important. The comoving Ly$\alpha$ luminosity density from IGM and galaxies, $\dot \rho_{{\rm Ly}\alpha}^{\rm IGM} = 8.73(6.51) \times 10^{40} {\rm erg}{\rm s}^{-1}{\rm Mpc}^{-3}$ and $\dot \rho_{{\rm Ly}\alpha}^{\rm ISM} = 6.62(3.21) \times 10^{40} {\rm erg}{\rm s}^{-1}{\rm Mpc}^{-3}$ at $z = 4(7)$, is consistent with recent SDSS determinations. We predict a power $k^3 P^{{\rm Ly}\alpha}(k, z)/2\pi^2 = 9.76\times 10^{-4}(2.09\times 10^{-5}){\rm nW}^2{\rm m}^{-4}{\rm sr}^{-2}$ at $z = 4(7)$ for $k = 0.1 h {\rm Mpc}^{-1}$.Comment: 14 Pages, 13 figure

Knowledge and Health Care resource allocation: CME/CPD course guidelines-based efficacy

Background: Most Health Care Systems consider Continuing Medical Education a potential tool to improve quality of care and reduce disease management costs. Its efficacy in general practitioners needs to be further explored. Objective: This study assesses the effectiveness of a one-year continuing medical education/continuing professional development course for general practitioners, regarding the improvement in knowledge of ARIA and GINA guidelines and compliance with them in asthma management. Methods: Sixty general practitioners, covering 68,146 inhabitants, were randomly allocated to continuing medical education/continuing professional development (five residential events + four short distance-learning refresher courses over one year) or no training. Participants completed a questionnaire after each continuing medical education event; key questions were repeated at least twice. The Local Health Unit prescription database was used to verify prescription habits (diagnostic investigations and pharmacological therapy) and hospitalizations over one year before and after training. Results: Fourteen general practitioners (46.7%) reached the cut-off of 50% attendance of the training courses. Knowledge improved significantly after training (p&lt;0.001, correct answers to key questions +13%). Training resulted in pharmaceutical cost containment (trained general practitioners +0.5% vs controls +18.8%) and greater attention to diagnosis and monitoring (increase in spirometry +63.4%, p&lt;0.01). Conclusion: This study revealed an encouraging impact of educational events on improvement in general practitioner knowledge of guidelines and daily practice behavioral changes. Long-term studies of large populations are required to assess the effectiveness of education on the behavior of physicians in asthma management, and to establish the best format for educational events

Knowledge and health care resource allocation: CME/CPD course guidelines-based efficacy.

BACKGROUND: Most health care systems consider continuing medical education a potential tool to improve quality of care and reduce disease management costs. Its efficacy in general practitioners needs to be further explored. OBJECTIVE: This study assesses the effectiveness of a one-year continuing medical education/continuing professional development course for general practitioners, regarding the improvement in knowledge of ARIA and GINA guidelines and compliance with them in asthma management. METHODS: Sixty general practitioners, covering 68,146 inhabitants, were randomly allocated to continuing medical education/continuing professional development (five residential events +four short distance-learning refresher courses over one year) or no training. Participants completed a questionnaire after each continuing medical education event; key questions were repeated at least twice. The Local Health Unit prescription database was used to verify prescription habits (diagnostic investigations and pharmacological therapy) and hospitalizations over one year before and after training. RESULTS: Fourteen general practitioners (46.7%) reached the cut-off of 50% attendance of the training courses. Knowledge improved significantly after training (p < 0.001, correct answers to key questions +13%). Training resulted in pharmaceutical cost containment (trained general practitioners +0.5% vs. controls +18.8%) and greater attention to diagnosis and monitoring (increase in spirometry +63.4%, p < 0.01). CONCLUSION: This study revealed an encouraging impact of educational events on improvement in general practitioner knowledge of guidelines and daily practice behavioral changes. Long-term studies of large populations are required to assess the effectiveness of education on the behavior of physicians in asthma management, and to establish the best format for educational events

Empowering line intensity mapping to study early galaxies

Line intensity mapping is a superb tool to study the collective radiation from early galaxies. However, the method is hampered by the presence of strong foregrounds, mostly produced by low-redshift interloping lines. We present here a general method to overcome this problem which is robust against foreground residual noise and based on the cross-correlation function $\psi_{\alpha L}(r)$ between diffuse line emission and Ly$\alpha$ emitters (LAE). We compute the diffuse line (Ly$\alpha$ is used as an example) emission from galaxies in a $(800{\rm Mpc})^3$ box at $z = 5.7$ and $6.6$. We divide the box in slices and populate them with $14000(5500)$ LAEs at $z = 5.7(6.6)$, considering duty cycles from $10^{-3}$ to $1$. Both the LAE number density and slice volume are consistent with the expected outcome of the Subaru HSC survey. We add gaussian random noise with variance $\sigma_{\rm N}$ up to 100 times the variance of the Ly$\alpha$ emission, $\sigma_\alpha$, to simulate foregrounds and compute $\psi_{\alpha L}(r)$. We find that the signal-to-noise of the observed $\psi_{\alpha L}(r)$ does not change significantly if $\sigma_{\rm N} \le 10 \sigma_\alpha$ and show that in these conditions the mean line intensity, $I_{Ly\alpha}$, can be precisely recovered independently of the LAE duty cycle. Even if $\sigma_{\rm N} = 100 \sigma_\alpha$, $I_\alpha$ can be constrained within a factor $2$. The method works equally well for any other line (e.g. HI 21 cm, [CII], HeII) used for the intensity mapping experiment.Comment: 5 pages, 4 figure

Empowering line intensity mapping to study early galaxies

Line intensity mapping is a superb tool to study the collective radiation from early galaxies. However, the method is hampered by the presence of strong foregrounds, mostly produced by low-redshift interloping lines. We present here a general method to overcome this problem which is robust against foreground residual noise and based on the cross-correlation function $\psi_{\alpha L}(r)$ between diffuse line emission and Ly$\alpha$ emitters (LAE). We compute the diffuse line (Ly$\alpha$ is used as an example) emission from galaxies in a $(800{\rm Mpc})^3$ box at $z = 5.7$ and $6.6$. We divide the box in slices and populate them with $14000(5500)$ LAEs at $z = 5.7(6.6)$, considering duty cycles from $10^{-3}$ to $1$. Both the LAE number density and slice volume are consistent with the expected outcome of the Subaru HSC survey. We add gaussian random noise with variance $\sigma_{\rm N}$ up to 100 times the variance of the Ly$\alpha$ emission, $\sigma_\alpha$, to simulate foregrounds and compute $\psi_{\alpha L}(r)$. We find that the signal-to-noise of the observed $\psi_{\alpha L}(r)$ does not change significantly if $\sigma_{\rm N} \le 10 \sigma_\alpha$ and show that in these conditions the mean line intensity, $I_{Ly\alpha}$, can be precisely recovered independently of the LAE duty cycle. Even if $\sigma_{\rm N} = 100 \sigma_\alpha$, $I_\alpha$ can be constrained within a factor $2$. The method works equally well for any other line (e.g. HI 21 cm, [CII], HeII) used for the intensity mapping experiment.Comment: 5 pages, 4 figure